5

11/07

Please read Cautions and warnings and

Important notes at the end of this document.

Reliability data

Test

Test methods/conditions

Requirement

Varistor voltage

The voltage between two terminals with

the specified measuring current applied

To meet the specified value.

Clamping voltage

The maximum voltage between two

terminals with the specified standard

impulse current (8/20

µs) applied.

To meet the specified value.

Surge current derating,

8/20

µs

CECC 42 000, test C 2.1

100 surge currents (8/20

µs), unipolar,

interval 30 s, amplitude corresponding

to derating curve for 100 impulses

at 20

µs

(measured in direction

of surge current)

No visible damage

Surge current derating,

2ms

CECC 42 000, test C 2.1

100 surge currents (2 ms), unipolar,

interval 120 s, amplitude corresponding

to derating curve for 100 impulses

at 2 ms

(measured in direction

of surge current)

No visible damage

Abnormal overvoltage test

UL1449, limited current abnormal over-

voltage test. Apply a high AC voltage

to ThermoFuse varistor, the amplitude

of overvoltage and current limit will be

adopted from UL1449 general instruc-

tion in section 37. The specimen will be

tested on a softwood surface covered

with a double layer of white tissue

paper. The specimen is to be loosely

draped with a double layer of cheese-

cloth. The cheesecloth shall cover

openings where flame, molten or other

particles may be expelled as a result of

the test. The test result will be visually

inspected.

Any of these phenomena

shall not be observed, or

this specimen will be

judged as failed part.

1. Emission of flame,

molten metal, glowing

or flaming particles

through any openings

(pre-existed or created

as a result of the test)

in the product.

2. Charring, glowing, or

flaming of the supporting

surface, tissue paper,

or cheesecloth.

3. Ignition of the enclosure.

4. Creation of any openings

in the enclosure that

result in accessibility of

live parts, when judged

in accordance with

accessibility of live parts,

UL1449 section 13.

ThermoFuse varistors, ETFV14 series

Housed varistors